CN111596268A

CN111596268A - Laser beam angle deviation detection device

Info

Publication number: CN111596268A
Application number: CN202010381324.XA
Authority: CN
Inventors: 李涛; 张昊伟; 梁洋洋; 王楠; 李国强
Original assignee: Shandong University
Current assignee: Shandong University
Priority date: 2020-05-08
Filing date: 2020-05-08
Publication date: 2020-08-28

Abstract

The invention discloses a laser beam angle deviation detection device, which comprises a beam splitter, a plano-convex lens, a plane reflector and two-dimensional position detectors, wherein the plane reflector is respectively arranged above, below and on the right of the beam splitter; and a plano-convex lens is arranged between the beam splitter and the right plane reflector, a first two-dimensional position detector and a second two-dimensional position detector are also arranged below the beam splitter, and the plano-convex lens, the plane reflector and the second two-dimensional position detector are arranged in such a way that the optical path of the light beam filtered by the beam splitter when passing through the plano-convex lens, the plane reflector and the second two-dimensional position detector is equal to the focal length of the plano-convex lens, namely, the detection surface of the two-dimensional position detector is ensured to be coincident with the focal plane of the plano-convex lens. The method has the advantages that the convex lens eliminates errors caused by space translation offset, tiny angle offset is amplified into a length offset on the two-dimensional position detector through the plano-convex lens, and the high-precision angle offset detection is realized through the high-precision two-dimensional position detector.

Description

Laser beam angle deviation detection device

Technical Field

The invention relates to the field of laser beam deviation detection, in particular to a laser beam angle deviation detection device.

Background

In optical systems, beam pointing accuracy is one of the important factors affecting system performance. The main reasons for the beam pointing deviation are various dynamic disturbances of the external environment, such as temperature changes, atmospheric turbulence, smog and dust, and mechanical vibrations like platform shaking and earth vibration. The disturbance caused by the bumping of the carrier can cause the directivity change of a laser radar emission beam, so that the laser radar has larger measurement error and even can not work normally. In order to achieve the measurement accuracy of the laser radar, it is necessary to ensure the stable light beam directivity of the radar on various carriers, and at present, two methods of overall stability and emission light path stability can be adopted. However, the laser radar has a large volume, so that the adoption of an overall stable method has great difficulty in the directional control precision and the manufacturing cost, and the cost is also high.

Disclosure of Invention

In order to overcome the above problems, the present application provides a high-precision beam offset detection for ultrafast laser, which can realize high-precision detection of beam angle offset. The technical proposal is that the method comprises the following steps,

a laser beam angle deviation detection device comprises a beam splitter, a plane reflector, a plano-convex lens and two-dimensional position detectors, wherein the plane reflector is respectively arranged above, below and on the right of the beam splitter; and a plano-convex lens is arranged between the beam splitter and the right plane reflector, a first two-dimensional position detector and a second two-dimensional position detector are also arranged below the beam splitter, and the plano-convex lens, the plane reflector and the second two-dimensional position detector are arranged in such a way that the optical path of the light beam filtered by the beam splitter when passing through the plano-convex lens, the plane reflector and the second two-dimensional position detector is equal to the focal length of the plano-convex lens, namely, the detection surface of the two-dimensional position detector is ensured to be coincident with the focal plane of the plano-convex lens.

Furthermore, the central positions of the beam splitter, the plano-convex lens and the plane mirror on the right side of the beam splitter are all on the same horizontal plane.

Furthermore, two plane mirrors arranged above and below the beam splitter are in a parallel state.

Furthermore, the two-dimensional position detector II forms a certain included angle with the horizontal line, so that the light beam reflected by the plane reflector can be conveniently received.

Furthermore, the first two-dimensional position detector and the second two-dimensional position detector are connected with an external upper computer through a detector controller, and signals of the angle offset of the light beam are sent to the upper computer.

Further, the beam splitter forms an included angle of 45 degrees with the horizontal line.

Advantageous effects

1) The method is simple and easy to implement, and can realize high-precision beam offset detection aiming at ultrafast laser;

2) the method can explore the processing potential of the space stable laser beam, reduce the laser processing error caused by the conventional environmental change and provide equipment support for high-quality manufacturing processes such as ultra-fast laser high depth-diameter ratio round hole manufacturing and the like; the requirements of miniaturization and fine production of devices in the military industry and the aerospace industry are met, and powerful support is provided for manufacturing the resistance reducing and reflection reducing structure of the key parts of the aerospace equipment.

Drawings

FIG. 1 is a schematic diagram of the structure;

FIG. 2 is an equivalent diagram of angular offset detection;

1-a beam splitter; 2-a plano-convex lens; 3-a plane mirror I; 4-a second plane reflector; 5-a plane mirror III; 6-a two-dimensional position detector I; 7-a two-dimensional position detector II; 8-detector controller.

Detailed Description

The following further description of the technology, in conjunction with the accompanying figures 1-2 and the specific embodiments, is provided to assist in understanding the present invention.

A laser beam angle deviation detection device comprises a beam splitter 1, a plane mirror and two-dimensional position detectors, wherein a first plane mirror 3, a second plane mirror 4 and a third plane mirror 5 are respectively arranged above, below and on the right of the beam splitter 1; the optical path of the light beam filtered by the beam splitter 1 when passing through the plano-convex lens 2, the first plane reflector 3, the second plane reflector 4, the third plane reflector 5 and the second two-dimensional position detector 7 is equal to the focal length of the plano-convex lens 2, so that the detection surface of the two-dimensional position detector is ensured to be coincident with the focal plane of the plano-convex lens.

The center positions of the beam splitter 1, the plano-convex lens 2 and the plane mirror III 5 on the right side of the beam splitter II are all on the same horizontal plane; the beam splitter 1 is at a 45 degree angle to the horizontal.

The first plane reflector 3 and the third plane reflector 5 are in a parallel state;

and the two-dimensional position detector II 6 forms a certain included angle with the horizontal line, so that the light beam reflected by the first plane reflector 3 can be conveniently received.

The first two-dimensional position detector 6 and the second two-dimensional position detector 7 are connected with an external upper computer through a detector controller 8, and signals of the angle offset of the light beam are sent to the upper computer.

Principle of operation

The two-dimensional position detector II 7 obtains the translational offset (x1, y1) of the light beam, the two-dimensional position detector I6 obtains the angular offset (x2, y2) of the light beam, and then the angular offset is transmitted to the upper computer 8 through the detector controller 8, so that high-precision light beam offset detection aiming at ultrafast laser is achieved.

FIG. 2 is an equivalent diagram of angular offset detection, on one hand, the plano-convex lens 2 functions to converge parallel light beams to eliminate errors caused by spatial translation offset, on the other hand, as shown in FIG. 1, the first plane mirror 3, the second plane mirror 4 and the third plane mirror 5 are used to increase optical paths, so that the optical path distance is consistent with the focal length of the plano-convex lens 2, even if the detection plane of the first two-dimensional position detector 6 coincides with the focal plane of the plano-convex lens 2, therefore, the optical paths of the first plane mirror 3, the second plane mirror 4 and the third plane mirror 5 can be equivalent to a straight light beam, as shown in FIG. 2, OD is the focal length 2m of the plano-convex lens 5, B point is the detection point of the second two-dimensional position detector 9, the angular offset of the light beam can be obtained according to the lengths of OD and BD, and even if the slight angular offset is a length of the plano-convex lens 5 of two meters, the optical path, therefore, the angular deviation detection with higher precision can be realized by the high-precision two-dimensional position detector.

Claims

1. A laser beam angle deviation detection device is characterized by comprising a beam splitter, a plano-convex lens, a plane reflector and two-dimensional position detectors, wherein the plane reflector is respectively arranged above, below and on the right of the beam splitter; and a plano-convex lens is arranged between the beam splitter and the right plane reflector, a first two-dimensional position detector and a second two-dimensional position detector are also arranged below the beam splitter, and the plano-convex lens, the plane reflector and the second two-dimensional position detector are arranged in such a way that the optical path of the light beam filtered by the beam splitter when passing through the plano-convex lens, the plane reflector and the second two-dimensional position detector is equal to the focal length of the plano-convex lens, so that the detection surface of the two-dimensional position detector is ensured to be coincident with the focal plane of the plano-convex.

2. The apparatus of claim 1, wherein the beam splitter, the plano-convex lens, and the plane mirror on the right side of the beam splitter are all centered on a horizontal plane.

3. The apparatus according to claim 1, wherein the two plane mirrors disposed above and below the beam splitter are parallel.

4. The apparatus of claim 1, wherein the two-dimensional position detector is disposed at an angle to the horizontal for receiving the light beam reflected from the plane mirror.

5. The device according to claim 1, wherein the first two-dimensional position detector and the second two-dimensional position detector are connected with an external upper computer through a detector controller, and send signals of the angular deviation of the light beam to the upper computer.

6. The apparatus of claim 1, wherein the beam splitter is at an angle of 45 degrees to the horizontal.